TY - GEN
T1 - Automated creation of overset grids directly from solid-model feature trees
AU - Dannenhoffer, John F.
AU - Davis, Roger L.
PY - 2009
Y1 - 2009
N2 - One of the challenges when generating overset grids is the decomposition of a configuration into the components around which the various grids will be generated. This step frequently requires that the analyst view the configuration and graphically select the surfaces that will form the boundaries of each grid. But increasingly, configurations are being generated through solid modelling systems, in which a configuration is generated by combining various primitives into the final configuration. Described herein is a technique for automatically generating overset grids directly from the solid-model feature tree. The basic idea here is to generate a structured grid inside and outside each primitive solid, which is fairly easy since most solid modelers use simple shapes for their primitives. Once all the grids have been generated, then the three Boolean operators - union, intersect, and difference - are used in the same way as they were used in generating the solid model. The only information needed here is the feature tree that is already stored in the solid model. A major difference between the new approach and conventional approaches is that the grid generation is directly coupled with the model generation and is not a separate process. The application of this new technique to several configurations are shown. First, the generality of the technique is demonstrated by showing the Boolean combination of two bodies for various relative body locations. Second, the technique is demonstrated on a automobile-like configuration; the ease with which the technique automatically adjusts itself based upon feature suppression is shown. Lastly, the use of the technique in conjunction with design optimization is shown.
AB - One of the challenges when generating overset grids is the decomposition of a configuration into the components around which the various grids will be generated. This step frequently requires that the analyst view the configuration and graphically select the surfaces that will form the boundaries of each grid. But increasingly, configurations are being generated through solid modelling systems, in which a configuration is generated by combining various primitives into the final configuration. Described herein is a technique for automatically generating overset grids directly from the solid-model feature tree. The basic idea here is to generate a structured grid inside and outside each primitive solid, which is fairly easy since most solid modelers use simple shapes for their primitives. Once all the grids have been generated, then the three Boolean operators - union, intersect, and difference - are used in the same way as they were used in generating the solid model. The only information needed here is the feature tree that is already stored in the solid model. A major difference between the new approach and conventional approaches is that the grid generation is directly coupled with the model generation and is not a separate process. The application of this new technique to several configurations are shown. First, the generality of the technique is demonstrated by showing the Boolean combination of two bodies for various relative body locations. Second, the technique is demonstrated on a automobile-like configuration; the ease with which the technique automatically adjusts itself based upon feature suppression is shown. Lastly, the use of the technique in conjunction with design optimization is shown.
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U2 - 10.2514/6.2009-3991
DO - 10.2514/6.2009-3991
M3 - Conference contribution
AN - SCOPUS:77958457221
SN - 9781563479755
T3 - 19th AIAA Computational Fluid Dynamics Conference
BT - 19th AIAA Computational Fluid Dynamics Conference
PB - American Institute of Aeronautics and Astronautics Inc.
ER -